TABLE 1.

Bacterial strains and plasmids used in this work

Strain or plasmid	Relevant phenotype and/or genotypea	Ref. or source
E. coli strains
DH5α	endA1 hsdR17 supE44 thi-1 recA1 gyrA(Nalr)	26
	relA1Δ(argF-lac) U169 depR φ80dlacΔ(lacZ)M15
M15	Strain for regulated high level expression with pQE vectors	Qiagen
Plasmids
pQE32	Apr, oriColE1, T5 promoter lac operator, λ to/E. coli rrnB T1 terminators, N-terminal His6	Qiagen
pQE32-His6BzdR	Apr, pQE32 derivative harboring the His6-bzdR gene under the control of T5 promoter lac operator	7
pQE32-His6BzdR3	Apr, pQE32 derivative harboring the His6-bzdR3 gene under the control of T5 promoter lac operator	This work
pQE32-His6BzdR4	Apr, pQE32 derivative harboring the His6-bzdR4 gene under the control of T5 promoter lac operator	This work
pQE32-His6BzdR5	Apr, pQE32 derivative harboring the His6-bzdR5 gene under the control of T5 promoter lac operator	This work
pQE32-His6BzdRΔL	Apr, pQE32 derivative harboring the His6-bzdRΔL gene under the control of T5 promoter lac operator	This work
pJCD-PN	Apr, pJCD01 derivative harboring a 585-bp EcoRI fragment that includes the PN promoter	6
pQE60-His6-FNR*	Apr, pQE60 derivative that harbors the His6-fnr* gene under the control of T5 promoter lac operator	6
pREP4	Kmr, plasmid that expresses the lacI repressor	Qiagen
pECOR7	Apr, pUC19 harboring a 7.1-kb EcoRI DNA fragment containing the bzdRNO genes	5
pGEM-Teasy	Apr, oriColE1, lacZα	Promega
pGEMT-BzdRΔL	Apr, pGEM-Teasy derivative harboring the BzdRΔL gene	This work

^a Ap^r, ampicillin-resistant, Km^r, kanamycin-resistant, Nal^r, nalidixic acid-resistant.